John, mixed bag of nasties here. Routing, addressing, and (of course)
the DNS. More fun than should be legal on a friday afternoon.
Routing: there is a varient here. Think about routing table slots.
If I get one, does it matter what the length of the prefix that I
put in it? There are other abstraction methods besides aggregation,
at least thats what some smart people are telling me.
The other bits will have to wait.
% * From an RIR, as PI space
%
% * From an ISP, as PD CIDR space. ISPs might sensibly
% decide to charge less (in money or aggravation) for
% space which no one intended to route. Or might not: the
% marketplace is good at sorting out these things, as long
% as the RIRs are willing to make allocations to ISPs that
% reflect the desirability of having addresses for
% isolated networks unique and reflecting the ISPs to
% which they might ultimately connect.
%
% * From some other process, as long-prefix, almost
% certainly unroutable, isolated space. This process
% could presumably be designed to be very lightweight in
% charges and administrative costs.
%
% So, while I'm very hesitant about anything that ties addressing
% (of any sort) to DNS names, I'm not convinced that Dave's
% suggestion is worth dismissing out of hand.
%
% Three additional observations:
%
% (i) Tony's response to my note seems, to me, to turn SL largely
% into a policy problem, not a technical one. We haven't have
% really good success binding policies into protocols. That
% doesn't convince me that we should never do so, but it does seem
% to argue for looking at alternatives, even radical ones.
%
% (ii) ISPs impose restrictions on their customers all the time
% and often even enforce them. Many of us consider some of these
% to be desirable (e.g., terms and conditions prohibiting
% spamming) and others less so (e.g., prohibitions against running
% server or peer-peer protocols over a cable network or address
% restrictions that force reasonably-architected LANs into NAT
% arrangements) but the conditions clearly exist.
%
% (iii) Yes, if I have an odd address and sufficient money, I can
% almost certainly convince some ISP to route it. But that ISP's
% leverage to get its peers to accept any long-prefix addresses it
% happens to offer and route them may be distinctly limited,
% especially if, by offering/announcing those addresses, it is
% violating a well-understood policy against doing such things.
% (For example, an RIR policy that made PI address allocations
% much more difficult for ISPs who were guilty of routing table
% pollution by short prefixes could really focus the attention.)
% So it seems to me to be plausible to suggest that the right
% place to prevent routing table explosion (or even "bloat") is in
% routing decisions and acceptance of announcements, and not in
% creating special address scopes.
%
% I also note that site local addresses open up a whole series of
% questions about "locality" and scope-range. Perhaps we also
% need "ISP-local" addresses (routing into one ISP's space, or
% part of it, but not to that ISP's peers or transit customers)
% and so on. The one thing that can be guaranteed about that sort
% of arrangement is an extension of the "pay enough and someone
% will route it" model will apply: If some ISP sees a potential
% competitive advantage in offering such a product (and
% addresses), the product will follow soon thereafter. And,
% again, I think that this suggests that we had better figures out
% how to deal with these things on a policy basis, not a
% protocol-imbedded special address scope one. We are almost
% certain to have the policy problem anyway and it is not clear
% that special cases for peculiar address scopes will buy us that
% much in addition.
%
% john
%
%
--
--bill
Opinions expressed may not even be mine by the time you read them, and
certainly don't reflect those of any other entity (legal or otherwise).